In the illustration you can see some of these brain cells.
[Illustration: BRAIN CELLS.] ~5.

The Nerves.~--Each cell has one or more branches.

Some of the branches are joined to the branches of other cells so as to unite the cells together, just as children take hold of one another's hands.

Other branches are drawn out very long.
~6.~ The long branches are such slender threads that a great number of them together would not be as large as a fine silk thread.

A great many of these fine nerve threads are bound up in little bundles which look like white cords.